1. Field of the Invention
The present invention relates to an optical apparatus. More particularly, the present invention relates to an optical apparatus with dual illuminating devices.
2. Description of Related Art
Refer to FIG. 1 and FIG. 2. An optical apparatus for observing objects in accordance with the prior art such as an optical microscope 500 comprises a body 510 and an illuminating device 520. The body 510 comprises an object stage 511 and a light hole 512. The light hole 512 is defined in the underside of the body 510 under the object stage 511.
The illuminating device 520 comprises a pivoting arm 521. The pivoting arm 521 has two ends through which one end is pivotally mounted on the body 510 and the other end suspends a lighting device 522. The lighting device 522 adopts a single light emitted diode (LED).
When the microscope 500 needs light illuminated from the upper side of the object stage 511, rotating the arm 521 relative to the body 510 enables the lighting device 522 to be suspended over the object stage 511 to illuminate objects on the object stage 511. Likewise, when the microscope 500 needs light illuminated from the underside of the object stage 511, rotating the arm 521 relative to the body 510 enables the lighting device 522 to be located under the object stage 511 to illuminate objects on the object stage 511 through the light hole 512.
However, the aforementioned lighting device 522 cannot provide sufficient illumination to meet the brightness requirements for observation when the lighting device 522 is located under the object stage 511 to illuminate objects on the object stage 511 through the light hole 512. The reason is that the light beams are transmitted into the body 510 though the light hole 512 from the outside of the object stage 511, and are transmitted from the underside of the body 510. It therefore provides weak illumination and cannot meet the brightness requirements for observation. Besides, underside illumination means that the body 510 of the microscope 500 needs to define the light hole 512. The light hole 512 not only influences the appearance of the entire microscope 500, but also results in unfavorable effects for preventing the optical lenses of the microscope 500 from dust.
Therefore, there is a need to provide an improved optical apparatus to mitigate or obviate the aforementioned problems.